Terminal and radio communication method

ABSTRACT

A terminal includes a receiving section that receives downlink control information for which cyclic redundancy check (CRC) bits are scrambled with use of a radio network temporary identifier (RNTI) common to one or more terminals, and a control section that controls reception of data associated with a multicast traffic channel (MTCH) with use of a physical downlink shared channel scheduled by the downlink control information in one or more bandwidth parts in a cell. Therefore, it is possible to appropriately control reception of multicast transmission using a physical downlink shared channel.

TECHNICAL FIELD

The present disclosure relates to a terminal and a radio communicationmethod in next-generation mobile communication systems.

BACKGROUND ART

In a Universal Mobile Telecommunications System (UMTS) network, thespecifications of Long-Term Evolution (LTE) have been drafted for thepurpose of further increasing high speed data rates, providing lowerlatency and so on (see Non-Patent Literature 1). In addition, for thepurpose of further high capacity, advancement and the like of the LTE(Third Generation Partnership Project (3GPP) Release (Rel.) 8 and Rel.9), the specifications of LTE-Advanced (3GPP Rel. 10 to Rel. 14) havebeen drafted.

Successor systems of LTE (e.g., referred to as “5th generation mobilecommunication system (5G),” “5G+ (plus),” “New Radio (NR),” “3GPP Rel.15 (or later versions),” and so on) are also under study.

CITATION LIST Non-Patent Literature

-   Non-Patent Literature 1: 3GPP TS 36.300 V8.12.0 “Evolved Universal    Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial    Radio Access Network (E-UTRAN); Overall description; Stage 2    (Release 8),” April, 2010

SUMMARY OF INVENTION Technical Problem

For future radio communication systems (hereinafter also referred to asNR), performing multicast transmission (also referred to as, forexample, a multicast traffic channel (MTCH), multicast data, or the likefor a logical channel) by using a physical downlink shared channel(e.g., a Physical Downlink Shared Channel (PDSCH)) is under study.Specifically, it is studied that the MTCH is mapped to a downlink sharedchannel (e.g., a Downlink Shared Channel (DL-SCH)) being a transportchannel and the DL-SCH is mapped to the PDSCH.

However, in existing LTE systems, multicast transmission is performedwith use of a physical multicast channel (PMCH). Thus, in NR, how aterminal controls reception of multicast transmission using a physicaldownlink shared channel becomes an issue.

In the light of this, the present disclosure has one object to provide aterminal and a radio communication method that can appropriately controlreception of multicast transmission using a physical downlink sharedchannel.

Solution to Problem

A terminal according to one aspect of the present disclosure includes areceiving section that receives downlink control information for whichcyclic redundancy check (CRC) bits are scrambled with use of a radionetwork temporary identifier (RNTI) common to one or more terminals, anda control section that controls reception of data associated with amulticast traffic channel (MTCH) with use of a physical downlink sharedchannel scheduled by the downlink control information in one or morebandwidth parts in a cell.

Advantageous Effects of Invention

According to one aspect of the present disclosure, it is possible toappropriately control reception of multicast transmission using aphysical downlink shared channel.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram to show an example of multicast transmission in asingle cell according to a first aspect;

FIG. 2 is a diagram to show an example of multicast transmission in aplurality of cells according to the first aspect;

FIG. 3 is a diagram to show an example of first scheduling of multicasttransmission according to a second aspect;

FIG. 4 is a diagram to show an example of second scheduling of multicasttransmission according to the second aspect;

FIG. 5 is a diagram to show an example of third scheduling of multicasttransmission according to the second aspect;

FIG. 6 is a diagram to show an example of beam control related tomulticast transmission according to a third aspect;

FIGS. 7A and 7B are diagrams to show an example of PDCP duplicationaccording to other aspects;

FIG. 8 is a diagram to show an example of a schematic structure of aradio communication system according to one embodiment;

FIG. 9 is a diagram to show an example of a structure of a base stationaccording to one embodiment;

FIG. 10 is a diagram to show an example of a structure of a userterminal according to one embodiment; and

FIG. 11 is a diagram to show an example of a hardware structure of thebase station and the user terminal according to one embodiment.

DESCRIPTION OF EMBODIMENTS (UE State)

In future radio communication systems (hereinafter also referred to asNR), it is assumed that a terminal (also referred to as a user terminal,User Equipment (UE), a device, and so on) has a plurality of statesdepending on traffic activity.

For example, the UE of NR may have three states such as an idle state,an inactive state, and a connected state in a radio resource control(RRC) layer. The states are also referred to as UE states, RRC states,and so on.

Here, the idle state is a state in which RRC connection between the UEand a base station is not established, and is also referred to as an RRCidle state (RRC_IDLE state), RRC idle (RRC_IDLE), and so on. The UE inthe idle state is required to perform a reconfiguration of the RRCconnection in order to transit to the connected state in which datatransfer can be performed.

The inactive state is a state in which the RRC connection between the UEand the base station is established, but data transfer cannot beperformed, and is also referred to as an RRC inactive state(RRC_INACTIVE state), RRC inactive (RRC_INACTIVE), and so on. The RRCconnection is established for the UE in the inactive state, and thus theUE in the inactive state can transit to the connected state quicker thanthe UE in the idle state. Therefore, delay time until a start of datatransfer is shorter than that of the UE in the idle state.

The connected state is a state in which the RRC connection between theUE and the base station is established and data transfer can beperformed, and is also referred to as an RRC connected state(RRC_CONNECTED state), RRC connected (RRC_CONNECTED), and so on. The UEin the connected state monitors a downlink control channel (e.g., aPhysical Downlink Control Channel (PDCCH)) for determination of whetherdata is scheduled, and thus power consumption of the UE is larger ascompared to that of the UE in the idle state or inactive state.

(Frequency Range)

For NR, supporting a plurality of frequency ranges (FRs) is also understudy. For example, a first FR (FR 1) is from 410 MHz to 7.125 GHz. Asecond FR (FR 2) is from 24.25 GHz to 52.6 GHz. A third FR (FR 3) isfrom 7.125 GHz to 24.25 GHz. A fourth FR (FR 4) is from 52.6 GHz to114.25 GHz. The UE may support at least one of the plurality of FRs.

(Multicast)

For NR, supporting unicast being a Point To Point (PTP) communicationscheme and multicast being a Point To Multipoint (PTM) communicationscheme is also under study.

In the multicast, identical contents are transmitted to one or moreterminals (also referred to as user terminals, User Equipments (UEs),devices, and so on) located in a specific area (also referred to as, forexample, a Multimedia Broadcast Multicast Service (MBMS) service areaand so on). The specific area may be constituted by a single cell or aplurality of cells. The multicast in which the specific area isconstituted by a single cell may be referred to as single cell(SC)-based PTM (SC-PTM) and so on. In a case of the SC-PTM, a pluralityof cells may cooperatively constitute the multicast.

Multicast transmission and unicast transmission may be performed (may betime-multiplexed) in different time units (e.g., slots) in an identicalcell. A time unit for performing multicast transmission in a radio framemay be determined in advance by specifications, or may be configured(notified) for the UE by higher layer signaling.

Note that in the present disclosure, it is only necessary that thehigher layer signaling is, for example, at least one of Radio ResourceControl (RRC) signaling, system information (e.g., at least one ofRemaining Minimum System Information (RMSI), Other system information(OSI), and System Information Block (SIB)), broadcast information (e.g.,Physical Broadcast Channel (PBCH) or Master Information Block (MIB)),Medium Access Control (MAC) signaling, and Radio Link Control (RLC)signaling.

Alternatively, each of multicast transmission and unicast transmissionmay be performed in a different cell. The UE that can perform carrieraggregation (CA) or dual connectivity (DC) may receive multicasttransmission in a given cell, and may receive or transmit unicasttransmission in another cell. Note that the UE that does not perform CAor DC may receive multicast transmission by being handed over to a cellin which multicast transmission is performed.

Note that the cell may be rephrased as a serving cell, a componentcarrier (CC), a carrier, and so on.

In multicast transmission, for example, a multicast traffic channel(MTCH), or an MTCH and a multicast control channel (MCCH) may be used asa logical channel.

On the MTCH, data to be multicast-transmitted (also referred to asmulticast data or traffic and so on) may be transferred. On the MCCH,control information necessary for MTCH reception may be transferred.Note that in the SC-PTM, the MTCH and MCCH may be referred to as anSC-MTCH and SC-MCCH or the like, respectively.

The MTCH and MCCH being the logical channel may be mapped to a downlinkshared channel (DL-SCH) being a transport channel in a Medium AccessControl (MAC) layer. The DL-SCH may be mapped to a physical downlinkshared channel (PDSCH) being a physical channel in a physical (PHY)layer.

Note that in unicast transmission, for example, a dedicated trafficchannel (DTCH), a dedicated control channel (DCCH), and the like may beused as the logical channel. The DTCH and DCCH may be mapped to theDL-SCH in the MAC layer, and the DL-SCH may be mapped to the PDSCH inthe physical layer. As described above, multicast transmission andunicast transmission may be associated with an identical type transportchannel and physical channel (in other words, the DL-SCH and PDSCH).

However, in existing LTE systems, multicast transmission is performedwith use of a physical multicast channel (PMCH). In NR, employing asystem structure different from the existing LTE systems, such asprovision of one or more bandwidth parts (BWPs) in a cell, is assumed.Thus, in NR, how the UE controls reception of multicast transmissionusing the PDSCH is an issue.

Thus, the inventors of the present invention studied a method forappropriately controlling reception of multicast transmission using thePDSCH in NR, and came up with the present invention.

Embodiments according to the present disclosure will be described indetail hereinafter with reference to the drawings. Note that in thepresent disclosure, multicast transmission, multicast, a multicastservice, multicast data, a service related to at least one of multicastand broadcast (multicast/broadcast) or multicast/broadcast, an MBMS, anMTCH, and the like may be interchangeably rephrased.

(First Aspect)

In a first aspect, support for multicast transmission in a single cellor a plurality of cells will be described.

<Single Cell>

A single cell supporting multicast transmission may be provided for eachcell group, may be provided for a specific cell group (e.g., a mastercell group (MCG)) or a secondary cell group (SCG), may be provided foreach FR, or may be provided for a specific FR.

The single cell may be a primary cell (PCell), a primary secondary cell(PSCell), a special cell (SpCell), a secondary cell (SCell) (PUCCHSCell) in which a physical uplink control channel (e.g., a PhysicalUplink Control Channel (PUCCH)) is transmitted, a cell with the lowestindex in each cell group or each FR, or a cell configured by RRCsignaling or system information (e.g., SIB20) for multicast.

In a case of DC, the SpCell may be the PCell in the MCG or the PSCell inthe SCG. In a case of anything other than DC, (in a case of CA or asingle cell, for example), the SpCell may be the PCell.

A given type multicast transmission may be supported in the whole singlecell, or may be supported in one or more bandwidth parts (BWPs) in thesingle cell. The BWP is a partial band in the cell.

The BWP in which multicast transmission is supported may be an initialBWP (also referred to as an initial downlink BWP, an initial downlinkactive BWP, and so on), or may be a BWP specified by at least one ofhigher layer signaling and L1 signaling (physical layer signaling).

For example, the BWP in which multicast transmission is provided for oneor more UEs (or a group including the one or more UEs) in at least oneof the idle state and the inactive state (idle/inactive state) may beany one of the following.

Initial BWP, and

BWP determined on the basis of at least one of system information (e.g.,SIB20) for multicast, information (MCCH information) transferred on anMCCH, and DCI.

The BWP in which multicast transmission is provided for one or more UEs(or a group including the one or more UEs) in a connected state may beany one of the following.

Initial BWP,

the first BWP in a cell (BWP with the lowest index (index value)), and

BWP determined on the basis of system information (e.g., SIB20) formulticast, RRC signaling (also referred to as an RRC parameter, an RRCIE, an RRC message, and so on), or L1 signaling (e.g., at least one ofinformation (MCCH information) transferred on an MCCH and DCI).

Note that in the present disclosure, it is only necessary that theinformation transferred on the MCCH is information for reception ofmulticast transmission (e.g., an MTCH). The information for reception ofthe multicast transmission (MTCH) may be information transferred on atleast one of a PDCCH and PDSCH, or may be rephrased as information to beRLC-signaled and so on, and is not always limited to the informationtransferred on the MCCH.

FIG. 1 is a diagram to show an example of multicast transmission in thesingle cell according to the first aspect. In FIG. 1, for example, it isassumed that the UE performs CA or DC using a plurality of cells (here,cells #0 to #2). Here, in cell #0 being a PCell, it is assumed that agiven type (here, type a) multicast transmission is supported.

As shown in FIG. 1, one or more BWPs are included in cell #0. In atleast one BWP in cell #0, multicast transmission may be supported. Forexample, in FIG. 1, an initial BWP (BWP #0) and BWPs #1 and #2 areincluded in cell #0, and a type a multicast service is supported in BWP#1.

Note that FIG. 1 is merely an illustrative example, and the number,types, and the like of BWPs in which multicast transmission is supportedin a single cell are not limited to those illustrated in the drawing. InFIG. 1, cells #0 and #1 are provided in FR 1 and cell #2 is provided inFR 2, but these are merely examples, and are not limited to thoseillustrated in the drawing. For example, cells #0 to #2 may belong to anidentical FR, or at least two of cells #0 to #2 may belong to FRsdifferent from each other.

<A Plurality of Cells/BWPs>

A plurality of cells supporting multicast transmission may be aplurality of cells belonging to cell groups different from each other,or may be a plurality of cells belonging to an identical cell group orto be aggregated by CA.

In each of the plurality of cells, multicast transmission may besupported in one or more BWPs. It is only necessary that the one or moreBWPs are determined in a manner similar to a single cell supporting theabove-described multicast transmission.

In the plurality of cells, different type multicast services may besupported. In a given carrier (or a given BWP with the given carrier),only a single type multicast service may be supported. Alternatively, ina given carrier (or a given BWP with the given carrier), a plurality oftypes of multicast services may be supported.

The different type multicast services may be associated with differentMTCHs. A multicast service type used in each cell (or each BWP) may benotified to the UE by at least one of higher layer signaling and L1signaling.

Specifically, the UE may receive information (multicast typeinformation) indicating the multicast service type for each cell (oreach BWP). The multicast type information may be notified by RRCsignaling (which may be an RRC parameter), may be included in systeminformation (e.g., SIB20), or may be included in information transferredon an MCCH.

FIG. 2 is a diagram to show an example of multicast transmission in theplurality of cells according to the first aspect. In FIG. 2, forexample, it is assumed that the UE performs CA or DC using a pluralityof cells (here, cells #0 to #3). Here, in cells #0 and #2 being PCells,it is assumed that a given type multicast service is supported.

For example, in FIG. 2, a type a multicast service and type b multicastservice are supported in cell #0, and a type c multicast service issupported in cell #2.

At least one of types supported in each cell supporting multicasttransmission may be supported in one or more BWPs. Among BWPs in anidentical cell, types to be supported may be identical to each other, orat least one type of the types may differ.

For example, whereas the type a multicast service and type b multicastservice are supported in BWP #1 for cell #0 of FIG. 2, the type amulticast service is supported and the type b multicast service is notsupported in BWP #2. In BWPs #0 to #2 for cell #2 of FIG. 2, anidentical type c multicast service may be supported.

Note that FIG. 2 is just an illustrative example, and the number ofcells supporting multicast transmission and the number, types, and thelike of BWPs in which multicast transmission is supported in each cellare not limited to those illustrated in the drawing. In FIG. 2, althoughcells #0 and #1 are in FR 1, cells #2 and #3 are in FR 2, and a cellsupporting multicast transmission for each FR is provided, which is justan illustrative example, and the present disclosure is not limited tothose illustrated in the drawing. For example, a cell supportingmulticast transmission for each cell group may be provided.

As described above, according to the first aspect, it is possible tosupport the multicast service in a BWP unit. Note that from theviewpoint of at least one of network management and utilizationefficiency (usage) of resources, for example, a BWP-relatedconfiguration, such as a BWP size, may be aligned between UEs havingdifferent capabilities.

(Second Aspect)

In a second aspect, a UE that receives multicast transmission andbehavior of the UE will be described.

The multicast transmission may be supported for one or more UEs in atleast one UE state of a connected state, an idle state, and an inactivestate. For example, the multicast transmission may be supported by atleast one UE of the following.

Only one or more UEs in connected state,

only one or more UEs in idle state,

only one or more UEs in inactive state, and

one or more UEs in at least two UE states of connected state, idlestate, and inactive state.

One or more UEs that receive the multicast transmission may support atleast one group of the following groups determined on the basis of a UEstate.

(1) a group including only UE(s) in a specific UE state (e.g., the idlestate, inactive state, or connected state),(2) either of a group including UE(s) in a first UE state (e.g., theidle/inactive state) or a group including UE(s) in a second UE state(e.g., the connected state), and(3) supporting both of a first group including UE(s) in a first UE state(e.g., the idle/inactive state) and a second group including UE(s) in asecond UE state (e.g., the connected state).

In a case of (3), configuration information (multicast configurationinformation) related to the multicast transmission may be identical (maybe common) or different from each other (may be dedicated) for theabove-described first group (e.g., the UE in the idle/inactive state)and second group (e.g., the UE in the connected state).

<Common Multicast Configuration Information>

For example, common multicast configuration information may be notifiedto the UE in the idle/inactive state and UE in the connected state bysystem information for multicast (e.g., SIB20). The common multicastconfiguration information may be notified with use of L1 signaling(e.g., at least one of information and DCI transferred via an MCCH) inaddition to the system information for multicast, or may be notifiedwith use of only the system information for multicast with no use of theL1 signaling.

<Dedicated Multicast Configuration Information>

The multicast configuration information relative to the UE in theidle/inactive state may be notified by system information (e.g., SIB20)for multicast. The multicast configuration information may be notifiedwith use of L1 signaling (e.g., at least one of information and DCItransferred via an MCCH) in addition to the system information formulticast, or may be notified with use of only the system informationfor multicast with no use of the L1 signaling.

On the other hand, the multicast configuration information for the UE inthe connected state may be notified by system information for multicast(e.g., SIB20). The multicast configuration information may be notifiedwith use of L1 signaling (e.g., at least one of information and DCItransferred via an MCCH) in addition to the system information formulticast, or may be notified with use of only the system informationfor multicast with no use of the L1 signaling.

Alternatively, the multicast configuration information for the UE in theconnected state may be notified by RRC signaling. The multicastconfiguration information may be notified with use of L1 signaling(e.g., at least one of information and DCI transferred via an MCCH) inaddition to the RRC signaling, or may be notified with use of only theRRC signaling with no use of the L1 signaling.

<Multicast Transmission Reception Behavior>

Next, reception behavior (scheduling) of multicast transmission for thegroups (e.g., the above-described (1) to (3)) as described above will bedescribed. For example, three scheduling methods below are assumed.

Scheduling of multicast transmission for the groups (e.g., theabove-described (1) to (3)) as described above will be described. Forexample, three scheduling methods below are assumed.

In first scheduling, the UE may receive system information for multicast(e.g., step S11 of FIG. 3), may receive an MCCH on the basis ofconfiguration information (MCCH configuration information) related tothe MCCH included in the system information (e.g., step S12 of FIG. 3),and may receive an MTCH on the basis of information (e.g., multicastconfiguration information) transferred on the MCCH (e.g., step S13 ofFIG. 3). The UE may be at least one of a UE in the idle state, a UE inthe inactive state, and a UE in the connected state.

In second scheduling, the UE may receive system information formulticast (e.g., step S21 of FIG. 4), and may receive an MTCH on thebasis of information (e.g., multicast configuration information)included in the system information (e.g., step S22 of FIG. 4). The UEmay be at least one of a UE in the idle state, a UE in the inactivestate, and a UE in the connected state.

In third scheduling, the UE may receive an RRC message (e.g., an RRCreconfiguration message) (e.g., step S31 of FIG. 5), and may receive anMTCH on the basis of information (e.g., multicast configurationinformation) included in the RRC message (e.g., step S32 of FIG. 5). TheUE may be a UE in the connected state.

In the first to third scheduling, the UE may receive the above-describedMTCH (multicast data) via a PDSCH scheduled by DCI CRC-scrambled by aspecific radio network temporary identifier (RNTI).

The specific RNTI may be an RNTI for each multicast service (eachmulticast service type). The specific RNTI may be referred to as, forexample, a group (G or GC)-RNTI, a single cell (SC)-RNTI, a multicast (Mor MC)-RNTI, a groupcast RNTI, and so on. A value of the G-RNTI may bethe same between UEs belonging to an identical group (e.g., theabove-described (1) to (3)).

One or more G-RNTIs may be introduced to a given UE. Each G-RNTI may beassociated with one or more types of multicast transmission supported bythe UE in a given cell or a plurality of cells.

For example, one or more G-RNTIs may be notified to the UE in theidle/inactive state with use of at least one of system information formulticast and L1 signaling (e.g., at least one of information and DCItransferred on an MCCH).

One or more G-RNTIs may be notified to the UE in the connected statewith use of at least one of system information for multicast, L1signaling (e.g., at least one of information and DCI transferred on anMCCH), and RRC signaling.

The maximum number X of G-RNTIs configurable for the given UE in a givencell or given BWP may be determined by specifications, or may beconfigured on the basis of a UE capability. For example, the maximumnumber X of G-RNTIs may be configured such that the maximum number Xdoes not exceed the UE capability reported from the UE.

<<First Scheduling>>

FIG. 3 is a diagram to show an example of the first scheduling ofmulticast transmission according to the second aspect. The firstscheduling shown in FIG. 3 may be applied to a group including at leastthe UE in the idle/inactive state. The group may include the UE in theconnected state, or need not include the UE in the connected state.

As shown in FIG. 3, at step S11, the UE may receive system informationfor multicast (e.g., SIB20). Specifically, at step S111, the UE maymonitor a search space (SS) set including one or more search spaces todetect a PDCCH (DCI) CRC-scrambled by a specific RNTI (e.g., a SystemInformation (SI)-RNTI).

At step S112, the UE may acquire the system information via a PDSCHscheduled by the DCI. The system information may include configurationinformation (MCCH configuration information) related to an MCCH.

The MCCH configuration information may include, for example, at leastone of a period (repetition period) of MCCH transmission, time offset,and a period (update period (modification period)) of update ofinformation transferred on the MCCH.

At step S12, the UE receives the MCCH on the basis of the MCCHconfiguration information in the system information. Specifically, atstep S121, the UE may monitor an SS set to detect a PDCCH (DCI)CRC-scrambled by a specific identifier.

The specific identifier may be a specific RNTI (e.g., a Single Cell(SC)-RNTI), or may be a temporary mobile group identifier. The specificidentifier may be included in the above-described MCCH configurationinformation.

At step S122, the UE may acquire the MCCH via the PDSCH scheduled by theDCI. The MCCH may be transmitted repetitively at the above-describedrepetition period. Identical information may be transmitted in the MCCHfor each repetition period within the update period. When theinformation transferred on the MCCH is to be changed, this change ofinformation transferred on the MCCH at the next update period may benotified at the last update period. The notification may be referred toas SC-MCCH change notification and so on.

The PDCCH may be used for the notification. The UE may controldiscontinuous reception (DRX) on the basis of the notification.Specifically, the UE may be activated while the notification isperformed, and may transit to a DRX state as long as the informationtransferred on the MCCH is not changed.

At steps S13 a and 13 b, the UE receives an MTCH on the basis ofconfiguration information (also referred to as MTCH configurationinformation, multicast configuration information, and so on) related toinformation (e.g., an MTCH (multicast)) transferred on the MCCH. Theinformation transferred on the MTCH configuration information mayinclude, for example, information indicating at least one of thefollowing.

G-RNTI,

payload size of DCI,

cell corresponding to multicast transmission,

BWP corresponding to multicast transmission,

multicast transmission type supported in each cell or BWP,

control resource set (CORESET) in which PDCCH to schedule PDSCH totransfer MTCH is mapped,

SS set used for monitoring of the PDCCH, and

configuration information (PDSCH configuration information) related toPDSCH to transfer MTCH.

At steps S131 a and S131 b, the UE may monitor the SS set to detect aPDCCH (DCI) CRC-scrambled by a specific RNTI (e.g., a G-RNTI). Note thatthe specific RNTI may be a different value for each multicasttransmission type. For example, FIG. 3 shows G-RNTI_a corresponding totype a multicast transmission and G-RNTI_b corresponding to type bmulticast transmission.

At steps S132 a and S132 b, the UE may acquire an MTCH corresponding toeach of the types a and b via the PDSCH scheduled by the DCI.

Note that steps S13 a and 13 b, steps S131 a and 131 b, and steps S132 aand 132 b are assumed to have different types of multicast transmission,but may include similar behavior.

<<Second Scheduling>>

FIG. 4 is a diagram to show an example of the second scheduling ofmulticast transmission according to the second aspect. The secondscheduling shown in FIG. 4 may be applied to a group including at leastthe UE in the idle/inactive state. The group may include the UE in theconnected state, or need not include the UE in the connected state.

Behavior at step S21 of FIG. 4 is similar to that at step S11 of FIG. 3.On the other hand, system information (e.g., SIB20) for multicastacquired at step S212 may include the above-described MTCH configurationinformation in place of the above-described MCCH configurationinformation. The information included in the MTCH configurationinformation is as described in the first scheduling.

At steps S22 a and 22 b, the UE receives an MTCH on the basis of MTCHconfiguration information in the system information acquired at stepS21. Note that details of steps S22 a and S22 b are similar to those ofsteps S13 a and S13 b of FIG. 3.

<<Third Scheduling>>

FIG. 5 is a diagram to show an example of the third scheduling ofmulticast transmission according to the second aspect. The thirdscheduling shown in FIG. 5 may be applied to a group including the UE inthe connected state. The group does not include the UE in theidle/inactive state.

At step S31 of FIG. 5, the UE may receive the above-described MTCHconfiguration information via RRC signaling. Specifically, at step S311,the UE may monitor an SS set including one or more search spaces todetect a PDCCH (DCI) CRC-scrambled by a UE-specific RNTI (e.g., a Cell(C)-RNTI).

At step S312, the UE may acquire the MTCH configuration information viathe PDSCH scheduled by the DCI. The MTCH configuration information maybe included in, for example, an RRC reconfiguration message. Theinformation included in the MTCH configuration information is asdescribed in the first scheduling.

At steps S32 a and 32 b, the UE receives an MTCH on the basis of MTCHconfiguration information in the system information acquired at stepS31. Note that details of steps S32 a and S32 b are similar to those ofsteps S13 a and S13 b of FIG. 3.

As described above, in NR, the MTCH (multicast data) is received on thebasis of the MCCH, system information for multicast, or MTCHconfiguration information included in the RRC message via the PDSCHscheduled by the PDCCH (DCI) CRC-scrambled by the G-RNTI.

As described above, according to the second aspect, it is possible toappropriately perform scheduling of multicast transmission for the UE ineach of the UE states (e.g., the idle state, inactive state, andconnected state).

(Third Aspect)

In a third aspect, UE behavior related to reception of at least one of aPDCCH and PDSCH related to multicast transmission will be described. TheUE behavior may be the same or different from each other as between atleast two of a UE in the idle state, a UE in the inactive state, and aUE in the connected state.

The UE behavior may include, for example, at least one of an assumptionof transmission configuration indicator (TCI) state (TCI state) forreception of an MTCH (or an MCCH and MTCH) and transmission control ofuplink control information (UCI).

<TCI State>

The TCI state may be, for example, information related toquasi-co-location (QCL) between a target channel (in other words, areference signal (RS) for the channel) and another signal (e.g., anotherreference signal (RS)). The TCI state may be referred to as a spatialreception parameter, spatial relation information (SRI), and so on. Itcan be said that the TCI state is information indicating a beam used fortransmission of the target channel.

QCL is an indicator indicating statistical properties of at least one ofthe signal and channel (signal/channel). For example, when a givensignal/channel and another signal/channel are in a relationship of QCL,it may be indicated that it is assumable that at least one of Dopplershift, a Doppler spread, an average delay, a delay spread, and a spatialparameter (e.g., a spatial reception parameter (spatial Rx parameter))is the same (the relationship of QCL is satisfied in at least one ofthese) between such a plurality of different signals/channels.

Note that the spatial reception parameter may correspond to a receivebeam of the UE (e.g., a receive analog beam), and the beam may beidentified on the basis of spatial QCL. The QCL (or at least one elementin the relationship of QCL) in the present disclosure may be interpretedas sQCL (spatial QCL).

The UE may determine at least one of a transmit beam (Tx beam) and areceive beam (Rx beam) of the signal/channel on the basis of the TCIstate or the QCL relationship of the signal/channel.

A channel for which the TCI state or spatial relationship is configured(specified) may be, for example, at least one of a PDSCH, a PDCCH, anuplink shared channel (Physical Uplink Shared Channel (PUSCH)), and anuplink control channel (Physical Uplink Control Channel (PUCCH)).

The RS to have the QCL relationship with the channel may be, forexample, at least one of a synchronization signal block (SSB), a channelstate information reference signal (CSI-RS), a reference signal formeasurement (Sounding Reference Signal (SRS), a CSI-RS for tracking(also referred to as a Tracking Reference Signal (TRS)), a referencesignal for QCL detection (also referred to as a QRS), and so on.

The SSB is a signal block including at least one of a primarysynchronization signal (PSS), a secondary synchronization signal (SSS),and a broadcast channel (Physical Broadcast Channel (PBCH)). The SSB maybe referred to as an SS/PBCH block.

The UE that receives multicast transmission may control, on the basis ofinformation (TCI state) related to QCL between a PDSCH (or antenna portfor a demodulation reference signal (DMRS) for the PDSCH) and a givenRS, reception of the PDSCH associated with at least one of an MTCH andMCCH (MTCH/MCCH).

For example, which beam (also referred to as a TCI state or QCLrelationship) the UE in the idle/inactive state uses to receive theabove-described PDSCH may be of the UE implementation, may be determinedon the basis of a detected SSB, or may be identical to that of systeminformation for multicast (e.g., SIB20).

Which beam (also referred to as a TCI state or QCL relationship) the UEin the connected state uses to receive the above-described PDSCH may bedetermined with use of at least one of RRC signaling, MAC signaling, andDCI. Note that the TCI state (QCL relationship) of the UE in theconnected state may be determined on the basis of informationtransferred by the system information for multicast.

Specifically, M (M≥1) pieces of TCI states for the PDSCH (M pieces ofQCL information for the PDSCH) may be notified (configured) to the UE byRRC signaling. Note that the number M of TCI states configured for theUE may be limited by at least one of UE capability and a QCL type.

DCI used for scheduling of a PDSCH may include a field indicating a TCIstate for the PDSCH (which may be referred to as, for example, a TCIfield, a TCI state field, and so on).

When TCI states greater than a given number (given number) (e.g., 8 whenthe TCI field is 3 bits) are configured for the UE by higher layersignaling, the given number of the TCI states may be activated (orspecified) with use of a MAC CE. A value of the TCI field in the DCI mayindicate one of the TCI states activated by the MAC CE.

FIG. 6 is a diagram to show an example of beam control related tomulticast transmission according to the third aspect. As shown in FIG.6, a base station (e.g., gNB) may perform multicast transmission byusing beam cycling of a plurality of beams (here, beams #1 to #4). Notethat the beam cycling may also be referred to as beam sweeping and soon, and beams transmitted from the base station may be switched on thebasis of time.

As shown in FIG. 6, each beam to perform multicast transmission may beassociated with a given RS or a resource for the given RS (e.g., an SSBor CSI-RS resource). For example, in FIG. 6, beams #1 to #4 may beassociated with SSBs #1 to #4 or CSI-RS resources #1 to #4,respectively.

For example, as shown in FIG. 6, when detecting SSBs #1 and #2transmitted by beams #1 and #2, respectively, the UE in theidle/inactive state may control reception of the PDSCH with anassumption (presumption) that an DMRS for the PDSCH is in the QCLrelationship with SSBs #1 and #2 transmitted by beams #1 and #2.

On the other hand, as shown in FIG. 6, the UE in the connected state mayreceive, by using RRC signaling, four TCI states respectively indicatingthat the DMRS for the PDSCH is in the QCL relationship with SSBs #1 to#4 (or CSI-RS resources #1 to #4) respectively transmitted by beams #1to #4.

The UE may control, on the basis of a TCI state indicated by a value ofa given field (e.g., the TCI field) in DCI (DCI CRC-scrambled by theabove-described G-RNTI) used for scheduling of the PDSCH, reception ofthe PDSCH with an assumption (presumption) that the DMRS for the PDSCHis in the QCL relationship with SSB #3 (or CSI-RS resource #3)transmitted by beam #3.

<UCI Transmission Control>

UCI may include at least one of transmission confirmation information(which may be referred to as, for example, Hybrid Automatic RepeatreQuest ACKnowledgement (HARQ-ACK), ACK/NACK, and so on) for the PDSCH,channel state information (CSI), and scheduling request (SR).

In NR, HARQ-ACK (HARQ-ACK for a PDSCH to transfer an MTCH or (MTCH andMCCH)) for multicast transmission may be supported, or may not besupported.

In NR, CSI feedback (CSI feedback for a PDSCH to transfer an MTCH or(MTCH and MCCH)) relative to multicast transmission may be supported, ormay not be supported. Note that the CSI feedback (transmission) may bereferred to as a CSI report and so on.

In NR, transmission of an RS (e.g., a sounding reference signal (SRS))for channel condition estimation for multicast transmission may besupported in time division duplex (TDD), or may not be supported.

For example, the UE in the idle/inactive state need not performtransmission of at least one of the above-described HARQ-ACK, the CSIreport, the above-described RS (e.g., an SRS) for channel conditionestimation. On the other hand, the UE in the connected/inactive statemay perform transmission of at least one of the above-describedHARQ-ACK, the CSI report, the above-described the RS (e.g., an SRS) forchannel condition estimation.

(Fourth Aspect)

In a fourth aspect, restrictions in multicast transmission will bedescribed.

In multicast transmission, a restriction on at least one of thefollowing may be configured for a PDSCH associated with an MTCH, or maynot be configured.

(4.1) the number of transport blocks (TBs),(4.2) the number of layers (also referred to as a rank),(4.3) the number of DMRS antenna ports (DMRS ports),(4.4) subcarrier spacing (SCS),(4.5) cyclic prefix (CP) length, and(4.6) at least one of modulation order and a transport block size (TBS).

For example, when the number of TBs (4.1) is restricted, only thespecific number of TBs (e.g., a single TB) may be transmitted in thePDSCH associated with the MTCH.

When the number of layers (4.2) is restricted, only the specific numberof layers (e.g., a single layer) may be transmitted in the PDSCHassociated with the MTCH.

When the number of DMRS ports (4.3) is restricted, only the specificnumber of DMRS ports (e.g., a single DMRS port) may be transmitted inthe PDSCH associated with the MTCH.

When the SCS (4.4) is restricted, only specific SCS (e.g., 120 kHz) maybe supported in the PDSCH associated with the MTCH. On the other hand,when the restriction on the SCS is not configured, not only the specificSCS but also another SCS (e.g., 15 kHz, 30 kHz, 60 kHz, 240 KHz, 480kHz, 960 kHz, and the like) may be supported in the PDSCH.

In a case of the specific SCS (4.5) (e.g., 15 kHz, 30 kHz, 120 kHz, 240kHz, 480 kHz, 960 kHz), a regular CP is applied to the PDSCH associatedwith the MTCH, but an expanded CP longer than the regular CP may not beapplied. Note that when the expanded CP is applied to the PDSCH,specific SCS (e.g., 60 kHz) may be applied to the PDSCH.

Alternatively, also in a case that the specific SCS (e.g., 15 kHz, 30kHz, 120 kHz, 240 kHz, 480 kHz, 960 kHz) is applied to the PDSCHassociated with the MTCH, not only the regular CP but also the expandedCP may be applied.

The modulation order of the PDSCH associated with the MTCH (4.6) may notbe expected to be greater than 2 or 4. Here, modulation order “2”corresponds to Quadrature Phase Shift Keying (QPSK), and modulationorder “4” corresponds to 16 Quadrature Amplitude Modulation (QAM). Inother words, 64 QAM whose modulation order is “6” and 256 QAM whosemodulation order is “8” may not be applied to the PDSCH.

At least one of a TBS and a modulation and coding scheme (MCS) indexapplied to the PDSCH associated with the MTCH may be specified on thebasis of at least one of system information for multicast (e.g., SIB20),RRC signaling (e.g., an RRC reconfiguration message or RRC resumemessage), and physical layer signaling (e.g., information or DCItransferred on a PDSCH associated with an MCCH). Note that the TBS maybe determined by the UE on the basis of an MCS index and the like.

According to the fourth aspect, it is possible to appropriately controltransmission or reception of the PDSCH associated with the MTCH.

(Other Aspects)

In other aspects, enhancement in multicast transmission will bedescribed.

The multicast transmission may be combined with at least one of thefollowing.

(5.1) a plurality of transmission and reception points (TRPs)(multi TRPs),(5.2) code block group (CBG)-based transmission,(5.3) semi-persistent scheduling (SPS), and(5.4) duplication in a Packet Data Convergence Protocol (PDCP) layer.

In a case of the multi TRPs (5.1), a PDSCH associated with an MTCH maybe transmitted from a plurality of TRPs.

The CBG (5.2) includes one or more code blocks (CBs). Each CB isconstituted by segmenting 1 TB. CBG-based transmission of the PDSCHassociated with the MTCH may be supported or configured. The CBG-basedtransmission may be configured on the basis of whether HARQ-ACK feedbackis supported or configured in the multicast transmission.

For example, when the HARQ-ACK feedback is supported or configured inthe multicast transmission, the CBG-based transmission of the PDSCHassociated with the MTCH may be configured. On the other hand, when theHARQ-ACK feedback is not supported or configured in the multicasttransmission, the CBG-based transmission of the PDSCH associated withthe MTCH may not be configured.

(5.3) SPS may be applied to the PDSCH associated with the MTCH. In thiscase, DCI (group DCI) to activate or release the SPS may be supported.The DCI may be CRC-scrambled by the above-described G-RNTI.

(5.4) data (data transferred on the MTCH) related to the multicasttransmission may be duplicated in the PDCP layer, and may be transmittedin a plurality of cells. Accordingly, the UE may select data transmittedin any one of the plurality of cells, or may combine data transmitted inat least two of the plurality of cells.

FIGS. 7A and 7B are diagrams to show an example of PDCP duplicationaccording to other aspects. For example, in FIGS. 7A and 7B, multicastdata associated with a given bearer (e.g., a multicast bearer) may beduplicated into two.

The two pieces of the multicast data may be mapped to two MTCHscorresponding to different cells #1 and #2 in an RLC layer,respectively. The two MTCHs are mapped to two DL-SCHs corresponding todifferent cells #1 and #2 in a MAC layer, respectively. The two DL-SCHsmay be mapped to two PDSCHs corresponding to different cells #1 and #2in an L1 layer, respectively.

As shown in FIG. 7A, both of a PDSCH corresponding to cell #1 and aPDSCH corresponding to cell #2 may be multicasted.

Alternatively, as shown in FIG. 7B, the PDSCH corresponding to cell #1may be multicasted, whereas the PDSCH corresponding to cell #2 may beunicasted.

(Radio Communication System)

Hereinafter, a structure of a radio communication system according toone embodiment of the present disclosure will be described. In thisradio communication system, the radio communication method according toeach embodiment of the present disclosure described above may be usedalone or may be used in combination for communication.

FIG. 8 is a diagram to show an example of a schematic structure of theradio communication system according to one embodiment. The radiocommunication system 1 may be a system implementing a communicationusing Long Term Evolution (LTE), 5th generation mobile communicationsystem New Radio (5G NR) and so on the specifications of which have beendrafted by Third Generation Partnership Project (3GPP).

The radio communication system 1 may support dual connectivity(multi-RAT dual connectivity (MR-DC)) between a plurality of RadioAccess Technologies (RATs). The MR-DC may include dual connectivity(E-UTRA-NR Dual Connectivity (EN-DC)) between LTE (Evolved UniversalTerrestrial Radio Access (E-UTRA)) and NR, dual connectivity (NR-E-UTRADual Connectivity (NE-DC)) between NR and LTE, and so on.

In EN-DC, a base station (eNB) of LTE (E-UTRA) is a master node (MN),and a base station (gNB) of NR is a secondary node (SN). In NE-DC, abase station (gNB) of NR is an MN, and a base station (eNB) of LTE(E-UTRA) is an SN.

The radio communication system 1 may support dual connectivity between aplurality of base stations in the same RAT (for example, dualconnectivity (NR-NR Dual Connectivity (NN-DC)) where both of an MN andan SN are base stations (gNB) of NR).

The radio communication system 1 may include a base station 11 thatforms a macro cell C1 of a relatively wide coverage, and base stations12 (12 a to 12 c) that form small cells C2, which are placed within themacro cell C1 and which are narrower than the macro cell C1. The userterminal 20 may be located in at least one cell. The arrangement, thenumber, and the like of each cell and user terminal 20 are by no meanslimited to the aspect shown in the diagram. Hereinafter, the basestations 11 and 12 will be collectively referred to as “base stations10,” unless specified otherwise.

The user terminal 20 may be connected to at least one of the pluralityof base stations 10. The user terminal 20 may use at least one ofcarrier aggregation (CA) and dual connectivity (DC) using a plurality ofcomponent carriers (CCs).

Each CC may be included in at least one of a first frequency band(Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2(FR2)). The macro cell C1 may be included in FR1, and the small cells C2may be included in FR2. For example, FR1 may be a frequency band of 6GHz or less (sub-6 GHz), and FR2 may be a frequency band which is higherthan 24 GHz (above-24 GHz). Note that frequency bands, definitions andso on of FR1 and FR2 are by no means limited to these, and for example,FR1 may correspond to a frequency band which is higher than FR2.

The user terminal 20 may communicate using at least one of time divisionduplex (TDD) and frequency division duplex (FDD) in each CC.

The plurality of base stations 10 may be connected by a wired connection(for example, optical fiber in compliance with the Common Public RadioInterface (CPRI), the X2 interface and so on) or a wireless connection(for example, an NR communication). For example, if an NR communicationis used as a backhaul between the base stations 11 and 12, the basestation 11 corresponding to a higher station may be referred to as an“Integrated Access Backhaul (IAB) donor,” and the base station 12corresponding to a relay station (relay) may be referred to as an “IABnode.”

The base station 10 may be connected to a core network 30 throughanother base station 10 or directly. For example, the core network 30may include at least one of Evolved Packet Core (EPC), 5G Core Network(5GCN), Next Generation Core (NGC), and so on.

The user terminal 20 may be a terminal supporting at least one ofcommunication schemes such as LTE, LTE-A, 5G, and so on.

In the radio communication system 1, an orthogonal frequency divisionmultiplexing (OFDM)-based wireless access scheme may be used. Forexample, in at least one of the downlink (DL) and the uplink (UL),Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM(DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA),Single Carrier Frequency Division Multiple Access (SC-FDMA), and so onmay be used.

The wireless access scheme may be referred to as a “waveform.” Notethat, in the radio communication system 1, another wireless accessscheme (for example, another single carrier transmission scheme, anothermulti-carrier transmission scheme) may be used for a wireless accessscheme in the UL and the DL.

In the radio communication system 1, a downlink shared channel (PhysicalDownlink Shared Channel (PDSCH)), which is used by each user terminal 20on a shared basis, a broadcast channel (Physical Broadcast Channel(PBCH)), a downlink control channel (Physical Downlink Control Channel(PDCCH)) and so on, may be used as downlink channels.

In the radio communication system 1, an uplink shared channel (PhysicalUplink Shared Channel (PUSCH)), which is used by each user terminal 20on a shared basis, an uplink control channel (Physical Uplink ControlChannel (PUCCH)), a random access channel (Physical Random AccessChannel (PRACH)) and so on may be used as uplink channels.

User data, higher layer control information, System Information Blocks(SIBs) and so on are communicated on the PDSCH. User data, higher layercontrol information and so on may be communicated on the PUSCH. TheMaster Information Blocks (MIBs) may be communicated on the PBCH.

Lower layer control information may be communicated on the PDCCH. Forexample, the lower layer control information may include downlinkcontrol information (DCI) including scheduling information of at leastone of the PDSCH and the PUSCH.

Note that DCI for scheduling the PDSCH may be referred to as “DLassignment,” “DL DCI,” and so on, and DCI for scheduling the PUSCH maybe referred to as “UL grant,” “UL DCI,” and so on. Note that the PDSCHmay be interpreted as “DL data”, and the PUSCH may be interpreted as “ULdata”.

For detection of the PDCCH, a control resource set (CORESET) and asearch space may be used. The CORESET corresponds to a resource tosearch DCI. The search space corresponds to a search area and a searchmethod of PDCCH candidates. One CORESET may be associated with one ormore search spaces. The UE may monitor a CORESET associated with a givensearch space, based on search space configuration.

One search space may correspond to a PDCCH candidate corresponding toone or more aggregation levels. One or more search spaces may bereferred to as a “search space set.” Note that a “search space,” a“search space set,” a “search space configuration,” a “search space setconfiguration,” a “CORESET,” a “CORESET configuration” and so on of thepresent disclosure may be interchangeably interpreted.

Uplink control information (UCI) including at least one of channel stateinformation (CSI), transmission confirmation information (for example,which may be also referred to as Hybrid Automatic Repeat reQuestACKnowledgement (HARQ-ACK), ACK/NACK, and so on), and scheduling request(SR) may be communicated by means of the PUCCH. By means of the PRACH,random access preambles for establishing connections with cells may becommunicated.

Note that the downlink, the uplink, and so on in the present disclosuremay be expressed without a term of “link.” In addition, various channelsmay be expressed without adding “Physical” to the head.

In the radio communication system 1, a synchronization signal (SS), adownlink reference signal (DL-RS), and so on may be communicated. In theradio communication system 1, a cell-specific reference signal (CRS), achannel state information-reference signal (CSI-RS), a demodulationreference signal (DMRS), a positioning reference signal (PRS), a phasetracking reference signal (PTRS), and so on may be communicated as theDL-RS.

For example, the synchronization signal may be at least one of a primarysynchronization signal (PSS) and a secondary synchronization signal(SSS). A signal block including an SS (PSS, SSS) and a PBCH (and a DMRSfor a PBCH) may be referred to as an “SS/PBCH block,” an “SS Block(SSB),” and so on. Note that an SS, an SSB, and so on may be alsoreferred to as a “reference signal.”

In the radio communication system 1, a sounding reference signal (SRS),a demodulation reference signal (DMRS), and so on may be communicated asan uplink reference signal (UL-RS). Note that DMRS may be referred to asa “user terminal specific reference signal (UE-specific ReferenceSignal).”

(Base Station)

FIG. 9 is a diagram to show an example of a structure of the basestation according to one embodiment. The base station 10 includes acontrol section 110, a transmitting/receiving section 120,transmitting/receiving antennas 130 and a communication path interface(transmission line interface) 140. Note that the base station 10 mayinclude one or more control sections 110, one or moretransmitting/receiving sections 120, one or more transmitting/receivingantennas 130, and one or more communication path interfaces 140.

Note that, the present example primarily shows functional blocks thatpertain to characteristic parts of the present embodiment, and it isassumed that the base station 10 may include other functional blocksthat are necessary for radio communication as well. Part of theprocesses of each section described below may be omitted.

The control section 110 controls the whole of the base station 10. Thecontrol section 110 can be constituted with a controller, a controlcircuit, or the like described based on general understanding of thetechnical field to which the present disclosure pertains.

The control section 110 may control generation of signals, scheduling(for example, resource allocation, mapping), and so on. The controlsection 110 may control transmission and reception, measurement and soon using the transmitting/receiving section 120, thetransmitting/receiving antennas 130, and the communication pathinterface 140. The control section 110 may generate data, controlinformation, a sequence and so on to transmit as a signal, and forwardthe generated items to the transmitting/receiving section 120. Thecontrol section 110 may perform call processing (setting up, releasing)for communication channels, manage the state of the base station 10, andmanage the radio resources.

The transmitting/receiving section 120 may include a baseband section121, a Radio Frequency (RF) section 122, and a measurement section 123.The baseband section 121 may include a transmission processing section1211 and a reception processing section 1212. The transmitting/receivingsection 120 can be constituted with a transmitter/receiver, an RFcircuit, a baseband circuit, a filter, a phase shifter, a measurementcircuit, a transmitting/receiving circuit, or the like described basedon general understanding of the technical field to which the presentdisclosure pertains.

The transmitting/receiving section 120 may be structured as atransmitting/receiving section in one entity, or may be constituted witha transmitting section and a receiving section. The transmitting sectionmay be constituted with the transmission processing section 1211, andthe RF section 122. The receiving section may be constituted with thereception processing section 1212, the RF section 122, and themeasurement section 123.

The transmitting/receiving antennas 130 can be constituted withantennas, for example, an array antenna, or the like described based ongeneral understanding of the technical field to which the presentdisclosure pertains.

The transmitting/receiving section 120 may transmit the above-describeddownlink channel, synchronization signal, downlink reference signal, andso on. The transmitting/receiving section 120 may receive theabove-described uplink channel, uplink reference signal, and so on.

The transmitting/receiving section 120 may form at least one of atransmit beam and a receive beam by using digital beam forming (forexample, precoding), analog beam forming (for example, phase rotation),and so on.

The transmitting/receiving section 120 (transmission processing section1211) may perform the processing of the Packet Data Convergence Protocol(PDCP) layer, the processing of the Radio Link Control (RLC) layer (forexample, RLC retransmission control), the processing of the MediumAccess Control (MAC) layer (for example, HARQ retransmission control),and so on, for example, on data and control information and so onacquired from the control section 110, and may generate bit string totransmit.

The transmitting/receiving section 120 (transmission processing section1211) may perform transmission processing such as channel coding (whichmay include error correction coding), modulation, mapping, filtering,discrete Fourier transform (DFT) processing (as necessary), inverse fastFourier transform (IFFT) processing, precoding, digital-to-analogconversion, and so on, on the bit string to transmit, and output abaseband signal.

The transmitting/receiving section 120 (RF section 122) may performmodulation to a radio frequency band, filtering, amplification, and soon, on the baseband signal, and transmit the signal of the radiofrequency band through the transmitting/receiving antennas 130.

On the other hand, the transmitting/receiving section 120 (RF section122) may perform amplification, filtering, demodulation to a basebandsignal, and so on, on the signal of the radio frequency band received bythe transmitting/receiving antennas 130.

The transmitting/receiving section 120 (reception processing section1212) may apply reception processing such as analog-digital conversion,fast Fourier transform (FFT) processing, inverse discrete Fouriertransform (IDFT) processing (as necessary), filtering, de-mapping,demodulation, decoding (which may include error correction decoding),MAC layer processing, the processing of the RLC layer and the processingof the PDCP layer, and so on, on the acquired baseband signal, andacquire user data, and so on.

The transmitting/receiving section 120 (measurement section 123) mayperform the measurement related to the received signal. For example, themeasurement section 123 may perform Radio Resource Management (RRM)measurement, Channel State Information (CSI) measurement, and so on,based on the received signal. The measurement section 123 may measure areceived power (for example, Reference Signal Received Power (RSRP)), areceived quality (for example, Reference Signal Received Quality (RSRQ),a Signal to Interference plus Noise Ratio (SINR), a Signal to NoiseRatio (SNR)), a signal strength (for example, Received Signal StrengthIndicator (RSSI)), channel information (for example, CSI), and so on.The measurement results may be output to the control section 110.

The communication path interface 140 may perform transmission/reception(backhaul signaling) of a signal with an apparatus included in the corenetwork 30 or other base stations 10, and so on, and acquire or transmituser data (user plane data), control plane data, and so on for the userterminal 20.

Note that the transmitting section and the receiving section of the basestation 10 in the present disclosure may be constituted with at leastone of the transmitting/receiving section 120, thetransmitting/receiving antennas 130, and the communication pathinterface 140.

The transmitting/receiving section 120 may transmit downlink controlinformation. The transmitting/receiving section 120 may transmit adownlink shared channel. Cyclic redundancy check (CRC) bits may bescrambled for the downlink control information with use of a radionetwork temporary identifier (RNTI) common to one or more terminals.

The transmitting/receiving section 120 may transmit the RNTI for eachmulticast service type.

When the user terminal 20 is in at least one of an idle state, aninactive state, and a connected state, the transmitting/receivingsection 120 may transmit information (e.g., the above-described MTCHconfiguration information or multicast configuration information) forreception of the data by using a physical downlink shared channelassociated with a multicast control channel (MCCH).

When the user terminal 20 is in at least one of the idle state, theinactive state, and the connected state, the transmitting/receivingsection 120 may transmit information (e.g., the above-described MTCHconfiguration information or multicast configuration information) forreception of the data by using system information for multicast.

When the user terminal 20 is in the connected state, thetransmitting/receiving section 120 may transmit information (e.g., theabove-described MTCH configuration information or multicastconfiguration information) for reception of the data by using radioresource control (RRC) signaling.

(User Terminal)

FIG. 10 is a diagram to show an example of a structure of the userterminal according to one embodiment. The user terminal 20 includes acontrol section 210, a transmitting/receiving section 220, andtransmitting/receiving antennas 230. Note that the user terminal 20 mayinclude one or more control sections 210, one or moretransmitting/receiving sections 220, and one or moretransmitting/receiving antennas 230.

Note that, the present example primarily shows functional blocks thatpertain to characteristic parts of the present embodiment, and it isassumed that the user terminal 20 may include other functional blocksthat are necessary for radio communication as well. Part of theprocesses of each section described below may be omitted.

The control section 210 controls the whole of the user terminal 20. Thecontrol section 210 can be constituted with a controller, a controlcircuit, or the like described based on general understanding of thetechnical field to which the present disclosure pertains.

The control section 210 may control generation of signals, mapping, andso on. The control section 210 may control transmission/reception,measurement and so on using the transmitting/receiving section 220, andthe transmitting/receiving antennas 230. The control section 210generates data, control information, a sequence and so on to transmit asa signal, and may forward the generated items to thetransmitting/receiving section 220.

The transmitting/receiving section 220 may include a baseband section221, an RF section 222, and a measurement section 223. The basebandsection 221 may include a transmission processing section 2211 and areception processing section 2212. The transmitting/receiving section220 can be constituted with a transmitter/receiver, an RF circuit, abaseband circuit, a filter, a phase shifter, a measurement circuit, atransmitting/receiving circuit, or the like described based on generalunderstanding of the technical field to which the present disclosurepertains.

The transmitting/receiving section 220 may be structured as atransmitting/receiving section in one entity, or may be constituted witha transmitting section and a receiving section. The transmitting sectionmay be constituted with the transmission processing section 2211, andthe RF section 222. The receiving section may be constituted with thereception processing section 2212, the RF section 222, and themeasurement section 223.

The transmitting/receiving antennas 230 can be constituted withantennas, for example, an array antenna, or the like described based ongeneral understanding of the technical field to which the presentdisclosure pertains.

The transmitting/receiving section 220 may receive the above-describeddownlink channel, synchronization signal, downlink reference signal, andso on. The transmitting/receiving section 220 may transmit theabove-described uplink channel, uplink reference signal, and so on.

The transmitting/receiving section 220 may form at least one of atransmit beam and a receive beam by using digital beam forming (forexample, precoding), analog beam forming (for example, phase rotation),and so on.

The transmitting/receiving section 220 (transmission processing section2211) may perform the processing of the PDCP layer, the processing ofthe RLC layer (for example, RLC retransmission control), the processingof the MAC layer (for example, HARQ retransmission control), and so on,for example, on data and control information and so on acquired from thecontrol section 210, and may generate bit string to transmit.

The transmitting/receiving section 220 (transmission processing section2211) may perform transmission processing such as channel coding (whichmay include error correction coding), modulation, mapping, filtering,DFT processing (as necessary), IFFT processing, precoding,digital-to-analog conversion, and so on, on the bit string to transmit,and output a baseband signal.

Note that, whether to apply DFT processing or not may be based on theconfiguration of the transform precoding. The transmitting/receivingsection 220 (transmission processing section 2211) may perform, for agiven channel (for example, PUSCH), the DFT processing as theabove-described transmission processing to transmit the channel by usinga DFT-s-OFDM waveform if transform precoding is enabled, and otherwise,does not need to perform the DFT processing as the above-describedtransmission process.

The transmitting/receiving section 220 (RF section 222) may performmodulation to a radio frequency band, filtering, amplification, and soon, on the baseband signal, and transmit the signal of the radiofrequency band through the transmitting/receiving antennas 230.

On the other hand, the transmitting/receiving section 220 (RF section222) may perform amplification, filtering, demodulation to a basebandsignal, and so on, on the signal of the radio frequency band received bythe transmitting/receiving antennas 230.

The transmitting/receiving section 220 (reception processing section2212) may apply a receiving process such as analog-digital conversion,FFT processing, IDFT processing (as necessary), filtering, de-mapping,demodulation, decoding (which may include error correction decoding),MAC layer processing, the processing of the RLC layer and the processingof the PDCP layer, and so on, on the acquired baseband signal, andacquire user data, and so on.

The transmitting/receiving section 220 (measurement section 223) mayperform the measurement related to the received signal. For example, themeasurement section 223 may perform RRM measurement, CSI measurement,and so on, based on the received signal. The measurement section 223 maymeasure a received power (for example, RSRP), a received quality (forexample, RSRQ, SINR, SNR), a signal strength (for example, RSSI),channel information (for example, CSI), and so on. The measurementresults may be output to the control section 210.

Note that the transmitting section and the receiving section of the userterminal 20 in the present disclosure may be constituted with at leastone of the transmitting/receiving section 220, thetransmitting/receiving antennas 230, and the communication pathinterface 240.

Note that the transmitting/receiving section 220 may receive, commonlyto or independently of a plurality of traffic types, information (RBGsize information) indicating a configuration used for a determination ofa size of a resource block group (RBG) used for allocation of afrequency domain resource for a downlink shared channel or an uplinkshared channel.

The transmitting/receiving section 220 may receive downlink controlinformation. The transmitting/receiving section 220 may receive adownlink shared channel. Cyclic redundancy check (CRC) bits may bescrambled for the downlink control information with use of a radionetwork temporary identifier (RNTI) common to one or more terminals.

The transmitting/receiving section 220 may receive the RNTI for eachmulticast service type.

When the user terminal 20 is in at least one of the idle state, theinactive state, and the connected state, the transmitting/receivingsection 220 may receive information (e.g., the above-described MTCHconfiguration information or multicast configuration information) forreception of the data by using a physical downlink shared channelassociated with a multicast control channel (MCCH).

When the user terminal 20 is in at least one of the idle state, theinactive state, and the connected state, the transmitting/receivingsection 220 may receive information (e.g., the above-described MTCHconfiguration information or multicast configuration information) forreception of the data by using system information for multicast.

When the user terminal 20 is in the connected state, thetransmitting/receiving section 220 may receive information (e.g., theabove-described MTCH configuration information or multicastconfiguration information) for reception of the data by using radioresource control (RRC) signaling.

The control section 210 may control reception of data associated with amulticast traffic channel (MTCH) using a physical downlink sharedchannel scheduled by the downlink control information in one or morebandwidth parts in a cell.

The control section 210 may control reception of the downlink controlinformation.

(Hardware Structure)

Note that the block diagrams that have been used to describe the aboveembodiments show blocks in functional units. These functional blocks(components) may be implemented in arbitrary combinations of at leastone of hardware and software. Also, the method for implementing eachfunctional block is not particularly limited. That is, each functionalblock may be realized by one piece of apparatus that is physically orlogically coupled, or may be realized by directly or indirectlyconnecting two or more physically or logically separate pieces ofapparatus (for example, via wire, wireless, or the like) and using theseplurality of pieces of apparatus. The functional blocks may beimplemented by combining softwares into the apparatus described above orthe plurality of apparatuses described above.

Here, functions include judgment, determination, decision, calculation,computation, processing, derivation, investigation, search,confirmation, reception, transmission, output, access, resolution,selection, designation, establishment, comparison, assumption,expectation, considering, broadcasting, notifying, communicating,forwarding, configuring, reconfiguring, allocating (mapping), assigning,and the like, but function are by no means limited to these. Forexample, functional block (components) to implement a function oftransmission may be referred to as a “transmitting section (transmittingunit),” a “transmitter,” and the like. The method for implementing eachcomponent is not particularly limited as described above.

For example, a base station, a user terminal, and so on according to oneembodiment of the present disclosure may function as a computer thatexecutes the processes of the radio communication method of the presentdisclosure. FIG. 11 is a diagram to show an example of a hardwarestructure of the base station and the user terminal according to oneembodiment. Physically, the above-described base station 10 and userterminal 20 may each be formed as a computer apparatus that includes aprocessor 1001, a memory 1002, a storage 1003, a communication apparatus1004, an input apparatus 1005, an output apparatus 1006, a bus 1007, andso on.

Note that in the present disclosure, the words such as an apparatus, acircuit, a device, a section, a unit, and so on can be interchangeablyinterpreted. The hardware structure of the base station 10 and the userterminal 20 may be configured to include one or more of apparatusesshown in the drawings, or may be configured not to include part ofapparatuses.

For example, although only one processor 1001 is shown, a plurality ofprocessors may be provided. Furthermore, processes may be implementedwith one processor or may be implemented at the same time, in sequence,or in different manners with two or more processors. Note that theprocessor 1001 may be implemented with one or more chips.

Each function of the base station 10 and the user terminals 20 isimplemented, for example, by allowing given software (programs) to beread on hardware such as the processor 1001 and the memory 1002, and byallowing the processor 1001 to perform calculations to controlcommunication via the communication apparatus 1004 and control at leastone of reading and writing of data in the memory 1002 and the storage1003.

The processor 1001 controls the whole computer by, for example, runningan operating system. The processor 1001 may be configured with a centralprocessing unit (CPU), which includes interfaces with peripheralapparatus, control apparatus, computing apparatus, a register, and soon. For example, at least part of the above-described control section110 (210), the transmitting/receiving section 120 (220), and so on maybe implemented by the processor 1001.

Furthermore, the processor 1001 reads programs (program codes), softwaremodules, data, and so on from at least one of the storage 1003 and thecommunication apparatus 1004, into the memory 1002, and executes variousprocesses according to these. As for the programs, programs to allowcomputers to execute at least part of the operations of theabove-described embodiments are used. For example, the control section110 (210) may be implemented by control programs that are stored in thememory 1002 and that operate on the processor 1001, and other functionalblocks may be implemented likewise.

The memory 1002 is a computer-readable recording medium, and may beconstituted with, for example, at least one of a Read Only Memory (ROM),an Erasable Programmable ROM (EPROM), an Electrically EPROM (EEPROM), aRandom Access Memory (RAM), and other appropriate storage media. Thememory 1002 may be referred to as a “register,” a “cache,” a “mainmemory (primary storage apparatus)” and so on. The memory 1002 can storeexecutable programs (program codes), software modules, and the like forimplementing the radio communication method according to one embodimentof the present disclosure.

The storage 1003 is a computer-readable recording medium, and may beconstituted with, for example, at least one of a flexible disk, a floppy(registered trademark) disk, a magneto-optical disk (for example, acompact disc (Compact Disc ROM (CD-ROM) and so on), a digital versatiledisc, a Blu-ray (registered trademark) disk), a removable disk, a harddisk drive, a smart card, a flash memory device (for example, a card, astick, and a key drive), a magnetic stripe, a database, a server, andother appropriate storage media. The storage 1003 may be referred to as“secondary storage apparatus.”

The communication apparatus 1004 is hardware (transmitting/receivingdevice) for allowing inter-computer communication via at least one ofwired and wireless networks, and may be referred to as, for example, a“network device,” a “network controller,” a “network card,” a“communication module,” and so on. The communication apparatus 1004 maybe configured to include a high frequency switch, a duplexer, a filter,a frequency synthesizer, and so on in order to realize, for example, atleast one of frequency division duplex (FDD) and time division duplex(TDD). For example, the above-described transmitting/receiving section120 (220), the transmitting/receiving antennas 130 (230), and so on maybe implemented by the communication apparatus 1004. In thetransmitting/receiving section 120 (220), the transmitting section 120 a(220 a) and the receiving section 120 b (220 b) can be implemented whilebeing separated physically or logically.

The input apparatus 1005 is an input device that receives input from theoutside (for example, a keyboard, a mouse, a microphone, a switch, abutton, a sensor, and so on). The output apparatus 1006 is an outputdevice that allows sending output to the outside (for example, adisplay, a speaker, a Light Emitting Diode (LED) lamp, and so on). Notethat the input apparatus 1005 and the output apparatus 1006 may beprovided in an integrated structure (for example, a touch panel).

Furthermore, these types of apparatus, including the processor 1001, thememory 1002, and others, are connected by a bus 1007 for communicatinginformation. The bus 1007 may be formed with a single bus, or may beformed with buses that vary between pieces of apparatus.

Also, the base station 10 and the user terminals 20 may be structured toinclude hardware such as a microprocessor, a digital signal processor(DSP), an Application Specific Integrated Circuit (ASIC), a ProgrammableLogic Device (PLD), a Field Programmable Gate Array (FPGA), and so on,and part or all of the functional blocks may be implemented by thehardware. For example, the processor 1001 may be implemented with atleast one of these pieces of hardware.

(Variations)

Note that the terminology described in the present disclosure and theterminology that is needed to understand the present disclosure may bereplaced by other terms that convey the same or similar meanings. Forexample, a “channel,” a “symbol,” and a “signal” (or signaling) may beinterchangeably interpreted. Also, “signals” may be “messages.” Areference signal may be abbreviated as an “RS,” and may be referred toas a “pilot,” a “pilot signal,” and so on, depending on which standardapplies. Furthermore, a “component carrier (CC)” may be referred to as a“cell,” a “frequency carrier,” a “carrier frequency” and so on.

A radio frame may be constituted of one or a plurality of periods(frames) in the time domain. Each of one or a plurality of periods(frames) constituting a radio frame may be referred to as a “subframe.”Furthermore, a subframe may be constituted of one or a plurality ofslots in the time domain. A subframe may be a fixed time length (forexample, 1 ms) independent of numerology.

Here, numerology may be a communication parameter applied to at leastone of transmission and reception of a given signal or channel. Forexample, numerology may indicate at least one of a subcarrier spacing(SCS), a bandwidth, a symbol length, a cyclic prefix length, atransmission time interval (TTI), the number of symbols per TTI, a radioframe structure, a particular filter processing performed by atransceiver in the frequency domain, a particular windowing processingperformed by a transceiver in the time domain, and so on.

A slot may be constituted of one or a plurality of symbols in the timedomain (Orthogonal Frequency Division Multiplexing (OFDM) symbols,Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, andso on). Furthermore, a slot may be a time unit based on numerology.

A slot may include a plurality of mini-slots. Each mini-slot may beconstituted of one or a plurality of symbols in the time domain. Amini-slot may be referred to as a “sub-slot.” A mini-slot may beconstituted of symbols less than the number of slots. A PDSCH (or PUSCH)transmitted in a time unit larger than a mini-slot may be referred to as“PDSCH (PUSCH) mapping type A.” A PDSCH (or PUSCH) transmitted using amini-slot may be referred to as “PDSCH (PUSCH) mapping type B.”

A radio frame, a subframe, a slot, a mini-slot, and a symbol all expresstime units in signal communication. A radio frame, a subframe, a slot, amini-slot, and a symbol may each be called by other applicable terms.Note that time units such as a frame, a subframe, a slot, mini-slot, anda symbol in the present disclosure may be interchangeably interpreted.

For example, one subframe may be referred to as a “TTI,” a plurality ofconsecutive subframes may be referred to as a “TTI,” or one slot or onemini-slot may be referred to as a “TTI.” That is, at least one of asubframe and a TTI may be a subframe (1 ms) in existing LTE, may be ashorter period than 1 ms (for example, 1 to 13 symbols), or may be alonger period than 1 ms. Note that a unit expressing TTI may be referredto as a “slot,” a “mini-slot,” and so on instead of a “subframe.”

Here, a TTI refers to the minimum time unit of scheduling in radiocommunication, for example. For example, in LTE systems, a base stationschedules the allocation of radio resources (such as a frequencybandwidth and transmit power that are available for each user terminal)for the user terminal in TTI units. Note that the definition of TTIs isnot limited to this.

TTIs may be transmission time units for channel-encoded data packets(transport blocks), code blocks, or codewords, or may be the unit ofprocessing in scheduling, link adaptation, and so on. Note that, whenTTIs are given, the time interval (for example, the number of symbols)to which transport blocks, code blocks, codewords, or the like areactually mapped may be shorter than the TTIs.

Note that, in the case where one slot or one mini-slot is referred to asa TTI, one or more TTIs (that is, one or more slots or one or moremini-slots) may be the minimum time unit of scheduling. Furthermore, thenumber of slots (the number of mini-slots) constituting the minimum timeunit of the scheduling may be controlled.

A TTI having a time length of 1 ms may be referred to as a “normal TTI”(TTI in 3GPP Rel. 8 to Rel. 12), a “long TTI,” a “normal subframe,” a“long subframe,” a “slot” and so on. A TTI that is shorter than a normalTTI may be referred to as a “shortened TTI,” a “short TTI,” a “partialor fractional TTI,” a “shortened subframe,” a “short subframe,” a“mini-slot,” a “sub-slot,” a “slot” and so on.

Note that a long TTI (for example, a normal TTI, a subframe, and so on)may be interpreted as a TTI having a time length exceeding 1 ms, and ashort TTI (for example, a shortened TTI and so on) may be interpreted asa TTI having a TTI length shorter than the TTI length of a long TTI andequal to or longer than 1 ms.

A resource block (RB) is the unit of resource allocation in the timedomain and the frequency domain, and may include one or a plurality ofconsecutive subcarriers in the frequency domain. The number ofsubcarriers included in an RB may be the same regardless of numerology,and, for example, may be 12. The number of subcarriers included in an RBmay be determined based on numerology.

Also, an RB may include one or a plurality of symbols in the timedomain, and may be one slot, one mini-slot, one subframe, or one TTI inlength. One TTI, one subframe, and so on each may be constituted of oneor a plurality of resource blocks.

Note that one or a plurality of RBs may be referred to as a “physicalresource block (Physical RB (PRB)),” a “sub-carrier group (SCG),” a“resource element group (REG),” a “PRB pair,” an “RB pair” and so on.

Furthermore, a resource block may be constituted of one or a pluralityof resource elements (REs). For example, one RE may correspond to aradio resource field of one subcarrier and one symbol.

A bandwidth part (BWP) (which may be referred to as a “fractionalbandwidth,” and so on) may represent a subset of contiguous commonresource blocks (common RBs) for given numerology in a given carrier.Here, a common RB may be specified by an index of the RB based on thecommon reference point of the carrier. A PRB may be defined by a givenBWP and may be numbered in the BWP.

The BWP may include a UL BWP (BWP for the UL) and a DL BWP (BWP for theDL). One or a plurality of BWPs may be configured in one carrier for aUE.

At least one of configured BWPs may be active, and a UE does not need toassume to transmit/receive a given signal/channel outside active BWPs.Note that a “cell,” a “carrier,” and so on in the present disclosure maybe interpreted as a “BWP”.

Note that the above-described structures of radio frames, subframes,slots, mini-slots, symbols, and so on are merely examples. For example,structures such as the number of subframes included in a radio frame,the number of slots per subframe or radio frame, the number ofmini-slots included in a slot, the numbers of symbols and RBs includedin a slot or a mini-slot, the number of subcarriers included in an RB,the number of symbols in a TTI, the symbol length, the cyclic prefix(CP) length, and so on can be variously changed.

Also, the information, parameters, and so on described in the presentdisclosure may be represented in absolute values or in relative valueswith respect to given values, or may be represented in anothercorresponding information. For example, radio resources may be specifiedby given indices.

The names used for parameters and so on in the present disclosure are inno respect limiting. Furthermore, mathematical expressions that usethese parameters, and so on may be different from those expresslydisclosed in the present disclosure. For example, since various channels(PUCCH, PDCCH, and so on) and information elements can be identified byany suitable names, the various names allocated to these variouschannels and information elements are in no respect limiting.

The information, signals, and so on described in the present disclosuremay be represented by using any of a variety of different technologies.For example, data, instructions, commands, information, signals, bits,symbols, chips, and so on, all of which may be referenced throughout theherein-contained description, may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orphotons, or any combination of these.

Also, information, signals, and so on can be output in at least one offrom higher layers to lower layers and from lower layers to higherlayers. Information, signals, and so on may be input and/or output via aplurality of network nodes.

The information, signals, and so on that are input and/or output may bestored in a specific location (for example, a memory) or may be managedby using a management table. The information, signals, and so on to beinput and/or output can be overwritten, updated, or appended. Theinformation, signals, and so on that are output may be deleted. Theinformation, signals, and so on that are input may be transmitted toanother apparatus.

Reporting of information is by no means limited to theaspects/embodiments described in the present disclosure, and othermethods may be used as well. For example, reporting of information inthe present disclosure may be implemented by using physical layersignaling (for example, downlink control information (DCI), uplinkcontrol information (UCI), higher layer signaling (for example, RadioResource Control (RRC) signaling, broadcast information (masterinformation block (MIB), system information blocks (SIBs), and so on),Medium Access Control (MAC) signaling and so on), and other signals orcombinations of these.

Note that physical layer signaling may be referred to as “Layer 1/Layer2 (L1/L2) control information (L1/L2 control signals),” “L1 controlinformation (L1 control signal),” and so on. Also, RRC signaling may bereferred to as an “RRC message,” and can be, for example, an RRCconnection setup message, an RRC connection reconfiguration message, andso on. Also, MAC signaling may be reported using, for example, MACcontrol elements (MAC CEs).

Also, reporting of given information (for example, reporting of “Xholds”) does not necessarily have to be reported explicitly, and can bereported implicitly (by, for example, not reporting this giveninformation or reporting another piece of information).

Determinations may be made in values represented by one bit (0 or 1),may be made in Boolean values that represent true or false, or may bemade by comparing numerical values (for example, comparison against agiven value).

Software, whether referred to as “software,” “firmware,” “middleware,”“microcode,” or “hardware description language,” or called by otherterms, should be interpreted broadly to mean instructions, instructionsets, code, code segments, program codes, programs, subprograms,software modules, applications, software applications, softwarepackages, routines, subroutines, objects, executable files, executionthreads, procedures, functions, and so on.

Also, software, commands, information, and so on may be transmitted andreceived via communication media. For example, when software istransmitted from a website, a server, or other remote sources by usingat least one of wired technologies (coaxial cables, optical fibercables, twisted-pair cables, digital subscriber lines (DSL), and so on)and wireless technologies (infrared radiation, microwaves, and so on),at least one of these wired technologies and wireless technologies arealso included in the definition of communication media.

The terms “system” and “network” used in the present disclosure can beused interchangeably. The “network” may mean an apparatus (for example,a base station) included in the network.

In the present disclosure, the terms such as “precoding,” a “precoder,”a “weight (precoding weight),” “quasi-co-location (QCL),” a“Transmission Configuration Indication state (TCI state),” a “spatialrelation,” a “spatial domain filter,” a “transmit power,” “phaserotation,” an “antenna port,” an “antenna port group,” a “layer,” “thenumber of layers,” a “rank,” a “resource,” a “resource set,” a “resourcegroup,” a “beam,” a “beam width,” a “beam angular degree,” an “antenna,”an “antenna element,” a “panel,” and so on can be used interchangeably.

In the present disclosure, the terms such as a “base station (BS),” a“radio base station,” a “fixed station,” a “NodeB,” an “eNB (eNodeB),” a“gNB (gNodeB),” an “access point,” a “transmission point (TP),” a“reception point (RP),” a “transmission/reception point (TRP),” a“panel,” a “cell,” a “sector,” a “cell group,” a “carrier,” a “componentcarrier,” and so on can be used interchangeably. The base station may bereferred to as the terms such as a “macro cell,” a small cell,” a “femtocell,” a “pico cell,” and so on.

A base station can accommodate one or a plurality of (for example,three) cells. When a base station accommodates a plurality of cells, theentire coverage area of the base station can be partitioned intomultiple smaller areas, and each smaller area can provide communicationservices through base station subsystems (for example, indoor small basestations (Remote Radio Heads (RRHs))). The term “cell” or “sector”refers to part of or the entire coverage area of at least one of a basestation and a base station subsystem that provides communicationservices within this coverage.

In the present disclosure, the terms “mobile station (MS),” “userterminal,” “user equipment (UE),” and “terminal” may be usedinterchangeably.

A mobile station may be referred to as a “subscriber station,” “mobileunit,” “subscriber unit,” “wireless unit,” “remote unit,” “mobiledevice,” “wireless device,” “wireless communication device,” “remotedevice,” “mobile subscriber station,” “access terminal,” “mobileterminal,” “wireless terminal,” “remote terminal,” “handset,” “useragent,” “mobile client,” “client,” or some other appropriate terms insome cases.

At least one of a base station and a mobile station may be referred toas a “transmitting apparatus,” a “receiving apparatus,” a “radiocommunication apparatus,” and so on. Note that at least one of a basestation and a mobile station may be device mounted on a moving object ora moving object itself, and so on. The moving object may be a vehicle(for example, a car, an airplane, and the like), may be a moving objectwhich moves unmanned (for example, a drone, an automatic operation car,and the like), or may be a robot (a manned type or unmanned type). Notethat at least one of a base station and a mobile station also includesan apparatus which does not necessarily move during communicationoperation. For example, at least one of a base station and a mobilestation may be an Internet of Things (IoT) device such as a sensor, andthe like.

Furthermore, the base station in the present disclosure may beinterpreted as a user terminal. For example, each aspect/embodiment ofthe present disclosure may be applied to the structure that replaces acommunication between a base station and a user terminal with acommunication between a plurality of user terminals (for example, whichmay be referred to as “Device-to-Device (D2D),” “Vehicle-to-Everything(V2X),” and the like). In this case, user terminals 20 may have thefunctions of the base stations 10 described above. The words “uplink”and “downlink” may be interpreted as the words corresponding to theterminal-to-terminal communication (for example, “side”). For example,an uplink channel, a downlink channel and so on may be interpreted as aside channel.

Likewise, the user terminal in the present disclosure may be interpretedas base station. In this case, the base station 10 may have thefunctions of the user terminal 20 described above.

Actions which have been described in the present disclosure to beperformed by a base station may, in some cases, be performed by uppernodes. In a network including one or a plurality of network nodes withbase stations, it is clear that various operations that are performed tocommunicate with terminals can be performed by base stations, one ormore network nodes (for example, Mobility Management Entities (MMEs),Serving-Gateways (S-GWs), and so on may be possible, but these are notlimiting) other than base stations, or combinations of these.

The aspects/embodiments illustrated in the present disclosure may beused individually or in combinations, which may be switched depending onthe mode of implementation. The order of processes, sequences,flowcharts, and so on that have been used to describe theaspects/embodiments in the present disclosure may be re-ordered as longas inconsistencies do not arise. For example, although various methodshave been illustrated in the present disclosure with various componentsof steps in exemplary orders, the specific orders that are illustratedherein are by no means limiting.

The aspects/embodiments illustrated in the present disclosure may beapplied to Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond(LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communicationsystem (4G), 5th generation mobile communication system (5G), FutureRadio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR),New radio access (NX), Future generation radio access (FX), GlobalSystem for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registeredtrademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20,Ultra-WideBand (UWB), Bluetooth (registered trademark), systems that useother adequate radio communication methods and next-generation systemsthat are enhanced based on these. A plurality of systems may be combined(for example, a combination of LTE or LTE-A and 5G, and the like) andapplied.

The phrase “based on” (or “on the basis of”) as used in the presentdisclosure does not mean “based only on” (or “only on the basis of”),unless otherwise specified. In other words, the phrase “based on” (or“on the basis of”) means both “based only on” and “based at least on”(“only on the basis of” and “at least on the basis of”).

Reference to elements with designations such as “first,” “second,” andso on as used in the present disclosure does not generally limit thequantity or order of these elements. These designations may be used inthe present disclosure only for convenience, as a method fordistinguishing between two or more elements. Thus, reference to thefirst and second elements does not imply that only two elements may beemployed, or that the first element must precede the second element insome way.

The term “judging (determining)” as in the present disclosure herein mayencompass a wide variety of actions. For example, “judging(determining)” may be interpreted to mean making “judgments(determinations)” about judging, calculating, computing, processing,deriving, investigating, looking up, search and inquiry (for example,searching a table, a database, or some other data structures),ascertaining, and so on.

Furthermore, “judging (determining)” may be interpreted to mean making“judgments (determinations)” about receiving (for example, receivinginformation), transmitting (for example, transmitting information),input, output, accessing (for example, accessing data in a memory), andso on.

In addition, “judging (determining)” as used herein may be interpretedto mean making “judgments (determinations)” about resolving, selecting,choosing, establishing, comparing, and so on. In other words, “judging(determining)” may be interpreted to mean making “judgments(determinations)” about some action.

In addition, “judging (determining)” may be interpreted as “assuming,”“expecting,” “considering,” and the like.

“The maximum transmit power” according to the present disclosure maymean a maximum value of the transmit power, may mean the nominal maximumtransmit power (the nominal UE maximum transmit power), or may mean therated maximum transmit power (the rated UE maximum transmit power).

The terms “connected” and “coupled,” or any variation of these terms asused in the present disclosure mean all direct or indirect connectionsor coupling between two or more elements, and may include the presenceof one or more intermediate elements between two elements that are“connected” or “coupled” to each other. The coupling or connectionbetween the elements may be physical, logical, or a combination thereof.For example, “connection” may be interpreted as “access.”

In the present disclosure, when two elements are connected, the twoelements may be considered “connected” or “coupled” to each other byusing one or more electrical wires, cables and printed electricalconnections, and, as some non-limiting and non-inclusive examples, byusing electromagnetic energy having wavelengths in radio frequencyregions, microwave regions, (both visible and invisible) opticalregions, or the like.

In the present disclosure, the phrase “A and B are different” may meanthat “A and B are different from each other.” Note that the phrase maymean that “A and B is each different from C.” The terms “separate,” “becoupled,” and so on may be interpreted similarly to “different.”

When terms such as “include,” “including,” and variations of these areused in the present disclosure, these terms are intended to beinclusive, in a manner similar to the way the term “comprising” is used.Furthermore, the term “or” as used in the present disclosure is intendedto be not an exclusive disjunction.

For example, in the present disclosure, when an article such as “a,”“an,” and “the” in the English language is added by translation, thepresent disclosure may include that a noun after these articles is in aplural form.

Now, although the invention according to the present disclosure has beendescribed in detail above, it should be obvious to a person skilled inthe art that the invention according to the present disclosure is by nomeans limited to the embodiments described in the present disclosure.The invention according to the present disclosure can be implementedwith various corrections and in various modifications, without departingfrom the spirit and scope of the invention defined by the recitations ofclaims. Consequently, the description of the present disclosure isprovided only for the purpose of explaining examples, and should by nomeans be construed to limit the invention according to the presentdisclosure in any way.

1. A terminal comprising: a receiving section that receives downlinkcontrol information for which cyclic redundancy check (CRC) bits arescrambled with use of a radio network temporary identifier (RNTI) commonto one or more terminals; and a control section that controls receptionof data associated with a multicast traffic channel (MTCH) with use of aphysical downlink shared channel scheduled by the downlink controlinformation in one or more bandwidth parts in a cell.
 2. The terminalaccording to claim 1, wherein the receiving section receives the RNTIfor each multicast service type.
 3. The terminal according to claim 1,wherein when the terminal is in at least one of an idle state, aninactive state, and a connected state, the receiving section receivesinformation for reception of the data by using a physical downlinkshared channel associated with a multicast control channel (MCCH). 4.The terminal according to claim 1, wherein when the terminal is in atleast one of an idle state, an inactive state, and a connected state,the receiving section receives information for reception of the data byusing system information for multicast.
 5. The terminal according toclaim 1, wherein when the terminal is in a connected state, thereceiving section receives information for reception of the data byusing radio resource control (RRC) signaling.
 6. A radio communicationmethod for a terminal, the radio communication method comprising:receiving downlink control information for which cyclic redundancy check(CRC) bits are scrambled with use of a radio network temporaryidentifier (RNTI) common to one or more terminals; and controllingreception of data associated with a multicast traffic channel (MTCH)with use of a physical downlink shared channel scheduled by the downlinkcontrol information in one or more bandwidth parts in a cell.
 7. Theterminal according to claim 2, wherein when the terminal is in at leastone of an idle state, an inactive state, and a connected state, thereceiving section receives information for reception of the data byusing a physical downlink shared channel associated with a multicastcontrol channel (MCCH).
 8. The terminal according to claim 2, whereinwhen the terminal is in at least one of an idle state, an inactivestate, and a connected state, the receiving section receives informationfor reception of the data by using system information for multicast. 9.The terminal according to claim 2, wherein when the terminal is in aconnected state, the receiving section receives information forreception of the data by using radio resource control (RRC) signaling.